Virtual reality (VR) integrates real-time computer graphics and body tracking devices to immerse a participant in a computer-generated virtual environment. VR exposure therapy has been successful in the treatment of anxiety disorders. This Phase I STTR project applies VR to the treatment of substance use disorders (SUDs). The economic, social, physical, and psychological impact of SUDs is devastating. Treatments of most SUDs are promising, although the success rate with crack cocaine users is not encouraging. In the largest study of psychosocial treatments of cocaine dependence, 50 percent of participants were still using cocaine at the 6-month assessment. Drug craving is important in perpetuating drug dependence and is associated with relapse. Environmental cues previously associated with crack cocaine use have consistently induced craving in human laboratory research, often called cue reactivity studies. The ability of these environmental cues to precipitate craving and physiologic activity in drug dependent individuals is thought to be a result of classical conditioning in which drug related stimuli, through repeated pairing with drug use, acquire the ability to elicit specific drug related responses. It follows, then, that repeatedly presenting drug related environmental cues not followed by drug should lead to a reduction in the reactivity through the process of extinction. Although it is clear that craving is likely to be a classically conditioned phenomenon that is related to relapse, limitations of the cue reactivity laboratory procedures currently in use may restrict the therapeutic utility of these approaches. Therefore, we propose to develop a new medium for providing cue exposure treatment for crack cocaine dependence. We propose to construct a virtual crack house with four virtual environments (rooms) designed to elicit crack cocaine craving to be used in cue exposure procedures. The specific aims of the proposed project include: 1) The development of virtual environments to support cue exposure therapy for crack cocaine dependence; and 2) The preliminary testing of the cocaine virtual environments developed compared to neutral environments as to their ability to elicit craving in crack cocaine users in an open clinical design with 10 crack cocaine dependent participants. The long-term objectives to be achieved in Phase II include the development and testing of the treatment of crack cocaine dependence using VR cue exposure therapy in a controlled design.